In recent years, with the continuous development and progress of science and technology, the structures and functions of mechanical equipment or devices have become increasingly complicated. Components are required to realize large volume, light weight and integration of structures and functions, which poses higher requirements and new challenges to manufacturing technologies. The manufacture of large-sized (exceeding 1000 mm in a certain direction) metal components with complicated structures, such as load carrying components with complicated inner holes and light components with complicated rib structures, has become the emphasis of the development of modern manufacturing technologies. For the large-sized metal components with complicated structures, large amount of cutting is required by a machining method. When the components have deep cavity and inner hole structures, manufacture cannot be realized by the machining method. When the large-sized complicated components are shaped by integral forming, due to large metal deformation resistance and large local flow resistance, the shaping of the large-sized components may be completed only by large tonnage equipment. Although loads required by shaping can be reduced by local loading or local shaping, due to the complexity of flow law of metal deformation, deep cavity and inner hole structures cannot be directly shaped by this method. In addition, the key factor that limits the integral forming of the large-sized complicated component is the difficulty in preparation of large-sized original stock (often dozens of or even hundreds of tons).
In order to achieve high efficiency and high precision manufacturing of the component with complicated structure, some new manufacturing methods, such as additive manufacturing technologies, have emerged. The traditional additive manufacturing technologies include stereolithography, laminar layering and lamination shaping, fused deposition, etc. The shaped materials are mainly plastic and paper. Because of the disadvantages of low strength, low plasticity and low tenacity, the plastic and the paper often cannot satisfy the use requirement of the actual structural component. In recent years, an additive manufacturing technology (i.e., metal 3D printing technology) for shaping metal materials has been gradually developed and applied. The shaping principle is: electron beams or laser beams are used to partition regions for the substrate material (in accordance with mathematical models of parts) for heating and melting to form small molten pools; metal powder materials are absorbed by the molten pools and then are connected with the substrate; and metal deposits are accumulated layer by layer to obtain parts. The components with complicated structures, such as titanium alloy bulkheads of aircraft engines, etc., can be shaped through the method. However, because the metal materials are continuously heated and cooled during 3D printing, large residual stress exists in the shaped parts, and the mechanical performance of the obtained parts cannot meet the design requirements. At the same time, the production efficiency of 3D printing method is very low, and it often takes months or even longer time to complete the shaping of the large-sized complicated components. In addition, the parts shaped by the method have poor surface quality, and the shaped parts shall be machined, but workpieces with complicated structures with deep cavity and inner hole cannot be cut subsequently.
Recently, on the basis of the traditional laminar layering and lamination method, a new additive manufacturing method of metal components, i.e., ultrasonic additive manufacturing method, has appeared. For example, an auxiliary heating ultrasonic rapid shaping method and device proposed in the application of patent for invention with the publication number of CN103600166A, literature “Study on rapid shaping method based on ultrasonic welding technology” (periodical: machine tool and hydraulic pressure, 2007, Volume 3, Issue 3), literature “Effect of Process Parameters on Bond Formation During Ultrasonic Consolidation of Aluminum Alloy 3003; Journal of Manufacturing systems, Volume 25, Issue 3” and literature “Development of Functionally Graded Materials by Ultrasonic Consolidation; doi:10.1016/j.cirpj.2010.07.006” have a research on shaping of the three-dimensional solid blocky actual part in a manner of ultrasonic consolidation of foil.
The principle of shaping the three-dimensional solid blocky actual part in the manner of ultrasonic consolidation of foil is: a layer of metal foil (with a general thickness of 0.1-0.2 mm) is connected with a next layer of substrate material through ultrasonic vibration; after connection, residual parts of the layer of metal foil are cut away in accordance with a mathematical model; then a layer of metal foil is paved on the layer of metal foil and is connected through ultrasonic vibration; and after repeating like this, a required part can be obtained. The shaping method is currently used for shaping small-sized metal parts or micro parts. However, because the metal foil with small thickness is adopted and is connected layer by layer, the production efficiency is very low and the method cannot be used for the manufacture of large-sized components with large thickness or height. At the same time, because the mechanical performance of metal foil is poor and the connection reliability between adjacent layers is poor, the practical use requirements for the large-sized components cannot be satisfied. In addition, large-breadth (length and width) metal foil with uniform mechanical performance and thickness cannot be prepared at present. To solve the problem that traditional machining, integral forming and the existing additive manufacturing method are difficult to obtain large-sized metal components with complicated special-shape structure and high-performance requirement, a new manufacturing method for large-sized metal components with complicated structures shall be established.